Photo and electroluminescence from fluorene containing copolymers

This paper demonstrates that although excimer formation in the photoluminescence (PL) and electroluminescence (EL) spectra of poly(fluorene) homo and copolymers seems to be a troublesome problem, this can be can eliminated for high polymers by incorporating a relatively small amount of anthracene into the polymer main chain linked via the 9,10-positions. These material give a colorfast emission for both PL and EL even after annealing. Given the desirable characteristics of DHF/ANT copolymers, a variety of copolymers containing electronic rich and/or electron deficient comonomers are prepared. The former leads to red-shifts in both the EL and PL while the latter lead to blue-shifts. In each case, the emission is colorfast and improved quantum efficiencies are observed when both monomers are incorporated in the same copolymer molecule.